Aluminum-alloy clad sheet

Abstract

There are provided an aluminum-alloy clad sheet and a clad sheet subjected to heating equivalent to brazing, which each have a high strength and an excellent erosion resistance and thus allow a reduction in thickness of a clad sheet subjected to heating equivalent to brazing such as an aluminum alloy radiator tube, and / or of a clad sheet such as an aluminum-alloy brazing sheet. An aluminum-alloy clad sheet or a clad sheet subjected to heating equivalent to brazing includes at least a core aluminum alloy sheet and an aluminum-alloy sacrificial anti-corrosive material cladded with each other, and is to be formed into a heat exchanger by brazing. The core aluminum alloy sheet includes a specified 3000 series composition. Furthermore, the strength and the erosion resistance of the core aluminum alloy sheet are improved through control of grain size distribution of precipitates having a size in a specified level in the core aluminum alloy sheet, or control of the average number density and the composition of dispersed particles therein.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to an aluminum-alloy clad sheet having high strength and excellent erosion resistance, which is used for an aluminum-alloy heat exchanger (hereinafter, aluminum may be referred to as Al).[0003]2. Description of Related Art[0004]To reduce weight of a motor vehicle body, aluminum alloy materials are increasingly used for the components of the motor vehicle, such as a heat exchanger component, in place of typically used copper alloy materials. An anti-corrosive aluminum alloy material formed of a multilayered clad sheet (sometimes referred to as clad material) is used for the aluminum alloy materials for a heat exchanger component. The clad sheet includes at least a core aluminum alloy sheet and an aluminum-alloy sacrificial anti-corrosive material cladded with each other. The clad sheet is a raw material for a heat exchanger, which is formed into a heat exchanger by brazing. Hence, a simply c...

AI Technical Summary

Benefits of technology

The patent text describes the composition of an aluminum alloy sheet used for brazing and other applications. The sheet contains various elements such as Fe, Mg, Si, and Mn, which are important for strength and corrosion resistance. The unlisted elements, such as B, can be present in small amounts without affecting the overall quality of the sheet. However, if the unlisted elements are present in larger amounts, it may increase the cost of production. Therefore, it is important to maintain the unlisted elements within certain ranges to ensure optimal performance and cost-effectiveness. The content of Si should be at least 0.2%, but not more than 0.5% to maintain strength and corrosion resistance. The content of Cu should be at least 0.05% to secure strength and improve corrosion resistance, but not more than 1.2% to prevent degradation in fatigue resistance. The content of Mn should be at least 0.5% to secure strength and improve fatigue failure resistance, but not more than 1.8% to maintain formability and prevent cracking during working. The content of Ti should be at least 0.03% to secure corrosion resistance, but not more than 0.3% to maintain formability. The content of Fe should be 1.0% or less to maintain optimal performance.

Problems solved by technology

For such a brazing sheet including the core having a small thickness of less than 0.17 mm, the above-described improvement ideas in the related art, such as control of the structure of the core aluminum alloy sheet, i.e., control of the average grain size and the number density of the fine precipitates, are in fact insufficient for achieving the demanded high strength and excellent erosion resistance.

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